What does it mean to be American?

Being abroad for the past 15 days has raised in me the question of what it means to be American. Since leaving the U.S., I've become more aware that there is a difference between being "American" and being "from the United States." "America" is not a country but a series of continents including North America, Central America and South America. The United States is the country I'm from within America, and everyone I've encountered has formed ideas about what the U.S. is like. In Germany, I had several great conversations with Germans about stereotypes of the U.S. and Germany, why these stereotypes exist, and to what extent they may or may not be true. On my trip, I've also met people from Belgium, Denmark, Turkey, Italy, Australia, Pakistan, Iran and the U.S., among other countries. I hadn't realized the extent of how much of a relationship-building experience it can be to discuss similarities, differences and stereotypes of our respective countries with people from other countries. Now that I have had some time to process my experiences in Germany, the question: "What does it mean to be U.S. American?" hit me while I was standing in the Remembrance Day crowd near Downing Street watching (on a huge TV screen but standing about 200 feet from) the Queen of England laying the wreath to commemorate fallen soldiers. I got into a conversation with the man behind me who I am guessing was an immigrant to the UK from either Africa or the West Indies. He told me more about the Remembrance Day tradition, and I explained to him the similarity of "Veterans Day" in the U.S. (without the same level of ceremonial, though!). I am guessing that this question will take a lifetime to answer and lay in the subtleties or stark differences in the frames of reference that define "culture."